1. Field of the Invention
The present invention relates to computer-related architectures for providing I/O path redundancy to storage devices, and, more particularly, to a method and apparatus for transparently and seamlessly integrating multi-pathing processes into host operating system environments.
2. Description of the Related Art
Multipath drivers provide system designers with the ability to develop redundant pathways that can support the seamless continuation of I/O communications despite the failure or degradation of some of the paths. However, a significant concern facing system integrators involves the ability to incorporate the multipathing functionality into the host operating system without impacting the performance and integrity of the operating system. In particular, it is important not to disrupt the operating system view and management of the I/O device space.
A related issue concerns the ability to embed a multipath driver into the host operating system (OS) in a manner that fosters portability. For example, it would be desirable to develop a multipath driver that could be ported from one operating system to the next while remaining relatively independent of the OS platform. However, conventional multipath drivers are tightly coupled to the operating system in view of their implementation at the top of the driver stack above the device driver.